Respect schema defaults. (#727)

If an event is not present in the tracking plan, we'll now lookup the schema defaults for the project.

If the event is disabled in the schema default, it will only be sent to the Segment integration (i.e. api.segment.io).

If the event is enabled in the schema default, it will be sent to all integrations.

Ref: https://paper.dropbox.com/doc/Schema-Client-Side-Defaults-DufdS8Ej43mnFXvvMqm1b

Ref: https://paper.dropbox.com/doc/Schema-Client-Side-Defaults-DufdS8Ej43mnFXvvMqm1b

Analytics/Classes/Integrations/SEGIntegrationsManager.m

@@ -424,6 +424,8 @@ + (BOOL)isTrackEvent:(NSString *)event enabledForIntegration:(NSString *)key inP
         } else {
             return NO;
         }
+    } else if (plan[@"track"][@"__default"]) {
+        return [plan[@"track"][@"__default"][@"enabled"] boolValue];
     }
 
     return YES;

AnalyticsTests/IntegrationsManagerTest.swift

@@ -8,11 +8,16 @@ class IntegrationsManagerTest: QuickSpec {
     describe("IntegrationsManager") {
       context("is track event enabled for integration in plan") {
 
-        it("returns true when plan is empty") {
+        it("returns true when there is no plan") {
           let enabled = SEGIntegrationsManager.isTrackEvent("hello world", enabledForIntegration: "Amplitude", inPlan:[:])
           expect(enabled).to(beTrue())
         }
 
+        it("returns true when plan is empty") {
+          let enabled = SEGIntegrationsManager.isTrackEvent("hello world", enabledForIntegration: "Mixpanel", inPlan:["track":[:]])
+          expect(enabled).to(beTrue())
+        }
+
         it("returns true when plan enables event") {
           let enabled = SEGIntegrationsManager.isTrackEvent("hello world", enabledForIntegration: "Mixpanel", inPlan:["track":["hello world":["enabled":true]]])
           expect(enabled).to(beTrue())
@@ -37,6 +42,16 @@ class IntegrationsManagerTest: QuickSpec {
           let enabled = SEGIntegrationsManager.isTrackEvent("hello world", enabledForIntegration: "Mixpanel", inPlan:["track":["hello world":["enabled":true, "integrations":["Mixpanel":false]]]])
           expect(enabled).to(beFalse())
         }
+
+        it("returns false when plan disables new events by default") {
+          let enabled = SEGIntegrationsManager.isTrackEvent("hello world", enabledForIntegration: "Mixpanel", inPlan:["track":["__default":["enabled":false]]])
+          expect(enabled).to(beFalse())
+        }
+
+        it("returns uses event plan rather over defaults") {
+          let enabled = SEGIntegrationsManager.isTrackEvent("hello world", enabledForIntegration: "Mixpanel", inPlan:["track":["__default":["enabled":false],"hello world":["enabled":true]]])
+          expect(enabled).to(beTrue())
+        }
       }
     }
   }